Knitting apparatus for producing pile fabric



' July 30, 1968 I A. BROOK 3,394,564

KNITTING APPARATUS FOR PRODUCING PILE FABRIC Filed Nov. 5, 1965 3 Sheets-Sheet 1 INVENTOR ARTHUR BROOK ATTORNEYS I KNITTING APPARATUS FOR PRODUCING FILE FABRIC Filed Nov. s, 1965 A. BROOK 3 Sheets-Sheet 2 6 I fl Q V VE V s Y K m M mw m W W w c R A m U 8. m R A M A. BROOK July 30, 1968 I KNITTING APPARATUS FOR PRODUCING PILE FABRIC 3 SheetsSheet 3 Filed Nov 3, 1965 INVENTOR. ARTHUR BROOK BY ATTORNEYS United States Patent 3,394,564 KNITTING APPARATUS FOR PRODUCING PILE FABRKC Arthur Brook, 2 Wedgewood Lane, Lawrence, N.Y. 11559 Filed Nov. 3, 1965, Ser. No. 506,178 2 Claims. (CI. 6693) ABSTRACT OF THE DISCLOSURE Knitting apparatus for producing long loops, short loops, and combinations thereof comprising a circular bank of radially adjustable sinkers, cam means for actuating the sinkers into a yarn-engaging position, and a pattern wheel for selectively actuating selected sinkers out of this position, the non-selected sinkers being unaffected thereby. All sinkers are subsequently caused to partake of a loop-forming stroke whereby the selected sinkers form short loops and the non-selected sinkers form long loops. The sinkers are provided with yarn-engaging means on the nibs thereof which produce the long loops; the short loops being formed on yarn-receiving surfaces behind the nibs.

The present invention relates generally to knitting apparatus, and more particularly to certain improvements in circular knitting apparatus which provide accurate control over loop length in the knitted fabric produced by such apparatus. Thus, the improved knitting apparatus hereof can readily produce knitted fabric with a wide variety of short and long loop designs. Further, the long loop product of the improved apparatus is particularly adapted to be finished by shearing because of the uniform length of the long loops.

In the knitted fabric art, it has long been an objective to provide apparatus capable of producing fabric having multi-length loop designs, and also a long loop product wherein there is little or no variation in the loop length. The commercial advantages of knitted fabric with loop designs are so obvious as to require no mention. The desirability of uniformity in the loop length of long loop knitted fabric is to facilitate the shearing of the loops at a height above the body of the fabric which provides a deep pile velour. When there are a significant number of non-uniform short loops missed during the shearing operation, the appearance of the fabric is seriously adversely affected. These short loops can of course be cut by shearing closer to the body of the fabric, but this substantially reduces the depth of the fabric pile and thus lessens the commercial value of the knitted fabric.

In US. Patent 1,790,832 issued to OLena on Feb. 3, 1931, there is described and illustrated a circular knitting apparatus representing the environment for the improvements of the present invention and also exemplifying the most popular prior art solution to the problem of achieving accurately controlled, multi-length loops during the production of knitted fabric. Basically, this solution involves the use of sinkers having different heights of threadreceiving surfaces and a mode of operation wherein the thread is looped over one of these surfaces during the knitting operation to provide a particular length of loop. In the operation of this known knitting apparatus, sliding and rotating cam means are employed to position each sinker relative to conventional thread depositing mechanisms so that the thread is looped about the desired height of thread-receiving surface, all in the manner illustrated and described in the O'Lena patent. Such knitting apparatus and generally all prior art knitting apparatus similarly relying on different heights of sinker surfaces to provide loop length control have not been found to be entirely Ice satisfactory, particularly as regards the uniformity of the long loops produced in the knitted fabric.

Basically, it is an object of the present invention to provide improved apparatus overcoming the foregoing and other shortcomings of the prior art. Specifically, it is an object to provide knitting apparatus characterized by a minimum of structural modifications and changes in mode of operation over current practice, but which as a consequence of these modifications and changes is capable of producing a greatly improved knitted product. One of the notable improvements is the uniformity in length of the long loops of the fabric which greatly facilitates the finishing of this fabric by shearing.

An improved knitting apparatus demonstrating features of the present invention employs as an improvement in the construction of the sinkers an appropriate thread-engaging means thereon, preferably located along the upper edge and at the free end of the nib of each sinker. Cooperating with this sinker construction is the usual sinker-actuating cam which, in particular, has a cam surface thereon effective to position each sinker, in turn, in a thread-engaging operative position wherein the thread is adapted to be deposited for engagement in such sinker thread-engaging means. The sinker-actuating cam includes another cam surface which when subsequently encountered actuates the sinker and engaged thread through inward radial movement to draw out the thread and ultimately produce a long loop thereof in the knitted fabric. This positive engagement of the thread and the provision for sinker and thread movement through a prescribed distance in the forming of each long loop has been found to contribute to a uniformity in the length of such loops which heretofore was not achieved by merely looping thread over a sinker thread-receiving surface.

The improved knitting apparatus hereof further in cludes sinker-actuating means in the form of a pattern wheel which is coordinated with the operation of the sinker actuating cam to engage with each sinker immediately after the positioning thereof in the thread-engaging operative position and prior to the final inward radial thrust of the sinker. This pattern wheel can be arranged to actuate the sinker out of the thread-engaging position in which instance the final inward radial thrust will not draw out the thread because of lack of engagement of the thread with the sinker thread-engaging structure. Instead, this thread is merely looped over an appropriate sinker threadreceiving surface and forms a short loop in the knitted fabric. Thus, depending on how the pattern wheel is arranged, a wide variety of short and long loop designs can be produced in the knitted fabric product.

The above brief description, as 'well as further objects, features and advantages of the present invention, will be more fully appreciated by reference to the following detailed description of a presently preferred, but nonetheless illustrative embodiment in accordance with the present invention, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a plan view of a segment of a bank of sinkers of the knitting apparatus hereof and of the means cooperating therewith for actuating each of the sinkers through radial movement;

FIG. 2 is an isolated plan view of the means of said knitting apparatus;

FIGS. 3 and 4 are substantially identical perspective views of the sinkers of the present apparatus in each of two different operative positions producing short loops and long loops, respectively, to wit:

FIG. 3 illustrates a radial position of movement of the sinkers for forming a short loop in the knitted fabrics; and

FIG. 4 illustrates the proper sinker radial position of movement for forming a long loop in the knitted fabric sinker-actuating in the knitted fabric, namely as in the case of the sinker shown in the foreground therein; and

FIG. 5 is a perspective view, on an enlarged scale, of a typical knitted product produced by the apparatus and best illustrates areas of short loops and of long loops therein.

Reference is now made to the drawings and in particular to FIG. 5 in which there is shown a sample of knitted fabric F having an area B formed with uniform short loops S and an area C formed with long loops L which are characterized by their uniform length. For reasons well understood in the art of knitted fabric, in any knitted fabric such as the sample piece P which is provided with controlled lengths of loops S, L, it is important that these lengths be uniform particularly when the knitted fabric F is intended to be finished by being sheared. Thus, to produce a knitted fabric F with sheared loops and of a deep surface pile (such fabric being commonly known as velour) requires uniform lOng loops L which are sheared by a transverse cut along the body of the fabric P, such as along the line DD of FIG. 5. It should be appreciated that if there is a lack of uniformity in the length of the loops L the transverse cut along line DD fail to remove the closed end of one or more of the shorter loops, thus seriously adversely affecting the appearance of the fabric. It is, of course, no solution to cut the loops L closer to the body of the fabric so that even the non-uniform short loops are sheared since this results in a substantial reduction in the depth of the pile and lessens the commercial value of the knitted fabric.

With the objective of providing a knitted fabric F with accurately controlled loop length, particularly in connection with long loops L, certain improvements are herein proposed for application to known knitting apparatus. Since except for the improvements which shall be explained in detail subsequently herein the knitting apparatus is otherwise substantially unchanged and well understood by those in the art both as to construction and mode of operation, only so much of this apparatus and mode of operation thereof as is necessary for a complete understanding of the present invention will be described. Referring now particularly to FIGS. 14, it will be understood that the knitting apparatus, herein generally designated 10, includes the usual circular arrangement of vertically reciprocating needles 12 having latches 14 which function in a well known manner in conjunction with a cooperating circular bank of sinkers, generally designated 16, to produce the knitted fabric F. The improvements of the present invention contemplate an improved construction for each of the sinkers 16 as well as improved means for actuating the sinkers 16 through radial movement in sequence with normal knitting operations of the apparatus so as to provide a conventionally knitted fiat body of fabric F with short loops S, long loops L, or designs having combinations of short and long loops S, L.

Reference is made first to FIGS. 1, 2 wherein a segment of the bank of sinkers 16 is illustrated in conjunction with the means for actuating each of these sinkers, in turn, in radial movement during the knitting operation. These sinker-actuating means include a circular arrangement of connecting members 18 having strategically located sinkeractuating earns 20 connected therebetween. This arrangement of connecting members and earns 18, 20 forms a rigid sinker cam ring and is operatively disposed in recesses 22 provided in the butt-end of each of the sinkers 16. The cam ring 18, 20 can be appropriately mounted for rotational movement in its operative position within the channel formed collectively by the sinker recesses 22 and the sinkers 16 maintained substantially stationary except for radial reciprocating movement. In the alternative, and as illustrated herein, the cam ring 18, 20 can be maintained stationary and the sinkers 16 mounted for rotational movement as indicated by the arrow B. In either case, each cam 20 is effective to actuate each sinker 16, in turn, in

radial movement by the caming action produced by the camming surfaces on the cam. In total, there are three such caming surfaces producing significant radial movement for each sinker 16. These include a first encountered cam surface 28a, a second encountered cam surface 201) on the opposite side of the cam 20, and a last encountered cam surface 20c on the same side of the body of the cam 20 and separated from cam surface 2012 by an intermediate cam dwell or flat surface 20d. As may best be appreciated by a comparison of FIGS. 1 and 3, the cam surface 20a cooperates with the rear wall 22a of each sinker recess 22 to actuate each sinker into an outermost radial position preparatory to the knitting operation. The knitting operation actually occurs during inward radial movement of the sinkers 16 as occurs when the front Wall 2211 of the sinker recesses 22 contact the cam surface 20b and 20c in the order just named. As a result of the camming action of cam surface 2% each sinker 16 is, in turn, actuated through radial movement from the outermost radial position into a thread-enegaging position exemplified by the radial position of the sinker specifically designated 16a in FIG. 1. This thread-engaging sinker position is that radial position which is occupied by each sinker 16 at the start of the cam dwell 20d, the position occupied by sinker 16a. The next significant radial position which is provided each sinker 16 by the cam 20 is the innermost radial position which results from the camming action of. the last encountered camming surface 200.

In addition to the circumfcrentially spaced sinkeractuating cams 20, there is also provided rotatably mounted pattern wheels 24 in meshing engagement with the butts 25 of the sinkers 16 and effective to selectively actuate each of the sinkers, in turn, in slight inward radial movement. To this end, each pattern wheel 24 is mounted for rotation about a shaft 26 and has circumferentially spaced radial notches 28 in the peripheral edge thereof. By virtue of the positioning of the fixed shaft 26, each wheel 24 has meshing engagement of the notches 28 therein with the butts 25 of the sinkers 16. Moreover, the relative location of each wheel 24 and cooperating sinkeractuating cam 20 is such that each sinker 16a at the start of the cam dwell 20d extends substantially radially of the wheel 24. That is, an imagainary line through the plane of sinker 16a would intersect the vertical axis of the shaft 26 and thus also the axis of rotation of each pattern wheel 24. Thus, each pattern wheel 24 is effective to modify or not modify the radial position of each sinker 16a at a point after such sinker has been actuated through movement by the cam surface 20b but prior to any movement which can be imparted to such sinker by the last encountered cam surface 20c. Whether the pattern wheel 24 does or does not modify the radial position of each sinker in the position of sinker 16a, which it will be recalled is the thread-engaging radial position, depends on whether or not a sinker-actuating jack 30 is positioned within the radial notch 28 meshing with the sinker. As is generally understood, such jacks or elements 30 are often force fit in some of the notches 28 to shorten the depth of these notches, although not for the purpose of loop control in the manner provided herein. Thus, if the particular one of the notches 28 aligning with the sinker 16a is provided with a jack 30 and accordingly has a correspondingly shortened depth, the movement of the sinker 16a through meshing engagement in the direction E with this jack-filled notch 28 will produce, in an obvious manner, a slight inward radial movement in the sinker 16a. It is contemplated in accordance with the present invention that this slight inward radial sinker movement control the length of the loops formed in the knitted fabric. With the sinker moved out of the threadengaging position previously supplied it by the cam surface 20b by virtue of this slight radial inward movement, the sinker produces a short loop S, whereas if the same sinker encountered an open notch 28 and thus was not disturbed or moved from said thread-engaging position,

such sinker would be effective in producing a uniform long loop L.

The foregoing may be best appreciated in conjunction with FIGS. 3, 4 which respectively illustrate the forming of a short loop S and a long loop L. These figures also best illustrate the novel construction of the sinkers 16 wherein each sinker is identically constructed and includes a main body 32 forward of the recess 22. The upper edge 34 of the body 32 serves as a thread-receiving surface for a lower thread 36 which as a resultof knitting movement of the needles 12 and sinkers 1'6 and with an upper thread 44 in a well understood knitting operation forms the loops of the knitted fabric F. Extending in an elevated position over the surface 34 and cooperating with such surface to form a conventional sinker throat 38 is a sinker nib 40. The upper edge 42 of the nib 40 functions as a thread-receiving surface for an upper thread 44 which during one of the contemplated modes of operation of the knitting apparatus is the surface over which the upper thread 44 is looped during the formation of the short loops S. Alternatively, the upper thread 44 during another contemplated phase of operation of the knitting apparatus 10 is also deposited in an appropriate threadengaging structure, generally designated 46, which is formed on each free end of each sinker nib 40. In a preferred form, each thread-engaging structure 46 consists of a notch machined in the free end of each nib and presenting a rear thread-engaging surface 48 which during forward radial movement of each sinker 16 is effective to engage and thus carry the thread 44 through the radial movement imparted to the sinker. In this manner, when the upper thread 44 is engaged in the thread-engaging notch 46 and the sinker subsequently encounters the cam surface c, the engaged thread is drawn out into a comparatively long work-in-process loop L during radially inward movement of the sinker. See for example the sinkers 16b, 0 shown in FIG. 4 and representing threadengaging sinkers at progressive positions of movement along the cam surface 200. Ultimately the upper thread 44 is drawn down by the needles 12 on opposite sides of each of the sinkers 16b, c through the bights 44a thereof and is cast off as stitches, in a conventional manner during the knitting operation of the needles 12 and these sinkers, in the form of comparatively long loops L in the knitted fabric F.

From the foregoing it should be readily apparent that whether a sinker 16 forms a short loop S or long loop L depends upon whether it engages a jack-filled notch 28 in the pattern wheel 24 or an empty notch 28 therein. Thus, a knitted fabric F can be produced entirely wlth short loops S, or entirely with long loops L, or with combinations of these different lengths of loops, depending only upon how the peripheral notches 28 of the pattern wheel 24 are arranged. In all instances, each sinker 16 having a thread-engaging means 46 formed in the free end of the nib 40 thereon is actuated by the cam surface 20b into the thread-engaging operative position wherein the conventional thread-guiding means during normal operation of the knitting apparatus 10 would deposit the upper thread 44 into the thread-engaging structure 46. When this radial position of the sinker is left undisturbed 'by virtue of the butt of this sinker meshing with an empty notch 28 of the pattern wheel 24, the upper thread 44 is actually deposited in the thread-engaging structure 46 and is drawn into a long loop L during subsequent radially inward movement imparted to the sinker by the last encountered cam surface 200 of the cam 20. By reason of the positive engagement of the sinkers '16 with the thread during formation of the long loops L it has been found that the length of these loops are uniform and that the long looped fabric which is produced readily lends itself to shearing in the production of deep pile velour. In arranging the improved knitting apparatus 10 hereof for the production of knitted fabric with short loops S either entirely or in combination with long loops L, it is necessary only to place an appropriate number of jacks 30 in those of the notches 28 where it is desired to produce a short loop S. When one of these jack-filled notches 28 engages with the butt 25 of a sinker 16, it will move this sinker slightly forward and out of the thread-engaging operative position into a position wherein the thread 44 is then laid down behind the threadengaging surface 48. Thus, when the sinker is actuated through additional inward radial movement when encountering the cam surface 200, the result is that the upper thread 44 is merely looped over the threadreceiving surface 42 and produces a short loop S in the fabric F.

From the foregoing it should be appreciated that the improvements of the present invention provide the fabric F not only with variation in the loop length, but also with greater uniformity in the loops, particularly the long loops L which are positively engaged by the sinkers during the knitting operation. Moreover, these improvements are capable of being incorporated in conventional knitting apparatus with little or no change being required in such apparatus, except for the modified elements for such apparatus herein specifically identified and described. Furthermore, these modifications need not be adhered to in the specific detail described and illustrated herein but may take other forms and still accomplish the intended results. For example, instead of a machined notch forming the thread-engaging structure 46 it should be readily apparent that other structure effective to engage with the thread and still permit casting off thereof during the normal knitting operation can also be employed. In other respects as well a latitude of modification, change and substitution is intended in the foregoing disclosure and in some instances some features of the invention will be employed without a corresponding use of other features. Accordingly, it is approprrate that the appended claims be construed broadly and in a manner consistent with the spirit and scope of the invention herein.

What is claimed is:

1. In a knitting apparatus the improvements for selectively knitting fabric with uniform long loops, short loops and combinations thereof comprising: a bank of sinkers, each having a body and at least one nib formed thereon, a thread-engaging means formed on the free end of said nib for producing long loops of thread engaged by said means, and a thread-receiving surface formed on said nib rearwardly of said thread-engaging means for producing short loops of thread laid thereon; at least one sinker-actuating cam cooperating with said bank of sinkers, said cam having camming surfaces formed thereon including a first cam surface operatively effective to actuate eac'h sinker, in turn, from an outermost radial position into a thread-engaging position, a second cam surface adjacent said first cam surface operatively effective to provide a dwell interval for each said sinker in said thread-engaging position, and a third cam surface adjacent said second cam surface operatively effective to actuate each said sinker through a radial loop-forming stroke; and a rotary pattern wheel operatively arranged relative to said sinkers and said sinker-actuating cam to engage with each sinker, in turn, in said thread-engaging position thereof during said dwell interval and operatively effective to selectively actuate selected sinkers in comparatively slight inward radial movement out of said thread-engaging position when it is desired to produce short loops but otherwise having no effect on the radial position of said sinkers, non-selected sinkers being unaffected by said rotary pattern wheel, whereby thread laid behind said thread-engaging means and on said threadreceiving surface as occurs after said comparatively slight inward radial movement of the selected sinkers produces short loops and thread engaged by said thread engaging means of non-selected sinkers in said thread-engaging position is drawn into long loops during movement of the sinkers from said thread-engaging position through said radial loop-forming stroke.

2. An improved knitting apparatus as defined in claim 1 wherein said thread-engaging means is a notch in the free end of said nib.

References Cited UNITED STATES PATENTS 1,790,832 2/1931 OLena 6693 2,276,705 3/1942 Smith 6693 2,284,454 5/1942 Smith 6693 XR ROBERT R. MACKEY, Primary Examiner. 

